Sustainable further utilisation of vinasse

The biofuel sponsorship programmes of many nations have triggered something of a boom in demand for agricultural land and raw materials in the last few years. Countries characterised by both strong population growth and food shortage have encountered particular competition between the use of land for biofuels and foodstuffs.

Set against this background, fuels produced from biomass have been facing increased criticism. Indeed, the competition between food crops and energy crops is leading to increased public awareness and debate.

Reference is also made to the environmental impact of the bioethanol production process, since this leaves behind significant residues, so-called vinasse or slurry, following distillation. Every litre of bioethanol produced from sugar cane or sugar beet also produces up to 15 litres of vinasse. And although the vinasse can be employed as a fertiliser, its low pH value and the non-sustainable fertiliser/disposal strategies with which it is used lead to contamination of soil and water, which in turn causes significant environmental problems. New strategies in the field of production technology are therefore required to balance the competing objectives of foodstuff and energy production.